AU2010200943B2 - Separation process - Google Patents

Abstract

Abstract of the disclosure A separation apparatus (1) for elongated piece goods (5), with at least two adjacently arranged screw conveyors (2) being provided for reliable separation and transfer of the piece goods, with the screw surfaces (21) of the screw conveyors (2) forming at least one common guide means (22) for the elongated piece goods (5). (Fig. 1)

Description

Pool Section 29 Regulation 3.2(2)) AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: Invention Title: Separation apparatus The following statement is a full description of this invention, including the best method of performing it known to us: P111AAAU/1107 Separation Apparatus The invention relates to conveyor systems and in particular to separation apparatus in a conveyor system for conveying elongated piece goods. Background of the Invention Separation apparatuses are used in conveyor systems for elongated piece goods for transitioning elongated piece goods form a transversal transport to a longitudinal transport orientation. The terms 'transversal' and 'longitudinal' are used to denote a transport direction transverse or coaxial with the longitudinal axis of the elongated piece goods, respectively. Thus the tenrs 'cross conveyor' and 'transversal conveyor' are also used interchangeably. Conveyor systems with separation apparatuses are known in the prior art. For example, patent documents US 3,168,183 A describes a conveyor system on which tree logs or other elongate wood pieces having a circular cross section are transported with a longitudinal axis perpendicular to the transport direction (thus transversal or cross transport). A discharge device is located at the end of the conveyor to displace and remove the elongate wood pieces from the conveyor. Patent document DE 3912008 A describes a separation device for elongate, circular cross-section wood pieces that are transported in transversal direction with these separation apparatus, the piece goods are stopped at the end of the transversal transport and ejected to the longitudinal transit by an ejection device. Finally, patent document DE 10151971 A describes a separation device for cross-section indexing of the tree logs. A disadvantageous aspect to ejector-type separation apparatus is that high loads are applied on the piece goods and the installation/equipment in effecting transfer of the piece goods form a transversal oriented conveying into a longitudinal conveying attitude. It is therefore an object of the present invention to provide a separation apparatus which at least attempts to address the above mentioned disadvantages. It is a further object to provide reliable separation and transfer of elongate piece goods, with the interval between the delivery of two successive piece goods able to be changed and predetermined at least in one area. It is 2 a yet further object to provide for the transfer from a transversal transport to a longitudinal transport in simple and rapid manner which protects the piece goods and the installation. Summary of the Invention The present invention provides in one aspect a conveyor system for elongated piece goods, comprising a first cross conveyor for transporting the elongated piece goods in transversal orientation in a first conveying direction, and a separation apparatus, located downstream in conveying direction of the elongated piece goods at the cross conveyor, for separating and removing the elongated piece goods delivered from the first cross conveyor, wherein the separation apparatus comprises at least two screw conveyors arranged next to one another, with screw surfaces of the at least two screw conveyors fonning at least one common guide for the elongated piece goods, the common guide being delimited at least on one side by a stop rail, wherein the stop rail is provided solely in that partial area of the separating apparatus facing the first cross conveyor. This leads to the advantage that one each of the piece goods can be received in the guide means of the screw conveyors, with the movement of the piece goods occurring by a continuous rotation of the screw conveyor, with the forces acting upon the installation being low as a result of the operation of the screw conveyor. The piece goods can be moved in a substantially even way, through which the forces acting upon the piece goods, especially by acceleration, can be kept at a low level. By changing the rotational speed of the screw conveyor, the interval between the deliveries of successive piece goods can be changed. Especially in the case of delivery to a longitudinal transporter (conveyor), the distance between the piece goods can thus be optimized in a simple way even in the case of differently long piece goods on the longitudinal transporter, and high throughput can be ensured. Furthermore, a drive of the piece goods in the longitudinal direction can further occur by rotation of the screw conveyors in the same direction. This drive in the longitudinal direction can be used in the transfer to a longitudinal transporter for building up a speed component in the direction of the longitudinal transporter, through which the stresses on the piece goods and the installations can be kept at a low level 2a in the transfer area. In the case of other embodiments, the drive in the longitudinal direction of the piece goods can also be used for aligning the piece goods in that the piece goods are moved against a stop rail. It can be provided in an especially advantageous way that the screw conveyors have a substantially conical basic body, which means that the basic body of the screw conveyors is arranged in a substantially conical way. The advantageous aspect is that the screw conveyors can be arranged with a horizontal rotational axis. It is further advantageous that the conveying speed of the elongated piece goods can increase while the rotational speed of the screw conveyors remains the same. As a result of these advantages, the separation apparatus can be arranged to offer long service life and the separating conveyance of the piece goods can occur in an especially reliable manner. Other aspects of the invention are explained in closer detail by reference to the accompanying drawings in which a merely preferred embodiment is shown by way of example. Brief Description of the Drawings Fig. 1 shows a transport system comprising a separation apparatus in accordance with a preferred embodiment of the invention in a top view; and Fig. 2 shows the transport system according to Fig. 1 in a side view. Detailed Description of Preferred Embodiment Figs. 1 and 2 show transport system 4 with a separation apparatus 1 for elongated piece goods, comprising at least two screw conveyors 2 arranged adjacent to one another, with the screw surfaces 21 of the screw conveyors 2 forming at least one common guide means 22 for the elongated piece goods 5. The separation apparatus 1 is used for separating successively delivered piece goods 5, especially elongated ones, from one another, which means singularizing the same. As a result 3 of the singularization by means of the separation apparatus 1, the piece goods 5 delivered successively by means of a first conveyor can be transferred individually to a second conveyor, with the piece goods 5 being arranged to substantially touch one another on or in the first conveyor, and with the piece goods 5 being arranged on the second conveyor in a substantially spaced manner in respect of one another, especially with a predeterminable distance. The two conveyors can be arranged as longitudinal transporters and/or transversal transporters. In particular, the first conveyor can be arranged as a first transversal transporter 31 and the second conveyor as a first longitudinal transporter 61. The lengths of the individual piece goods 5 can differ. Preferred embodiments of the elongated piece goods 5 are planks, timber sections, rods, logs, and/or round wood. Other elongated piece goods can also be provided in other embodiments. The elongated piece goods 5 can usually have a longitudinal extension of several meters. Preferably, the elongated piece goods 5 are arranged in a substantially straight line along their longitudinal extension. Similarly preferably, the cross section along the longitudinal extension is substantially constant, as can be the case for example in a plank, beam, section, tube, log and/or especially in round wood, with the log also being stripped of its bark. The screw conveyor 2 is preferably an elongated component of helical geometry and substantially straight longitudinal extension, and comprises at least one screw surface 21. In the operation of the separation apparatus 1, the screw conveyor 2 is rotated about an axis parallel to the longitudinal extension of the screw conveyor 2, which axis forms the rotational axis 24 of the screw conveyor 2. The screw surface 21 has a slope, with the slope being substantially the inclination of the screw surface in relation to the rotational axis 24, and a pitch corresponding to the slope and circumference. As a result of the slope, a conveying direction of the piece goods 5 to be conveyed is achieved by means of the rotational movement in the case of a stationary arrangement of the screw conveyor, with the direction of conveyance being influenced, 4 among other things, by the configuration of the screw surface 21 and the arrangement of the rotational axis 24. The screw conveyor 2 preferably has a longitudinal extension between one and one and a half pitches of the screw surface 21. The secure separation can thus be ensured. The separation duration of the piece goods 5 can be low and the throughput of the separation apparatus 1 can be high. The screw surface 21 of the screw conveyor 2 is usually arranged as a flat spiral component, especially a sheet, with the flat sheet being connected with the basic body 25 at a number of points. Figs. 1 and 2 show such a screw conveyor 2 which has a substantially cylindrical basic body 25. In other especially advantageous embodiments, the screw conveyor 2 can also have a substantially conical basic body 25, which means it can be arranged in a substantially conical way. Substantially conical base bodies 25 form all bodies which generate a conical surface during their rotation about the rotational axis 24. The conical basic body 25 can especially be arranged as a pyramid, a truncated pyramid, preferably a cone, more preferably a truncated cone, or by several suitably arranged longitudinal rods, i.e. several longitudinal rods which are substantially arranged along the conical surface. It is advantageous that the screw conveyors 2 can be arranged with a horizontal rotational axis 24 and the screw conveyors 2 can thus be held easily in a rotatable manner and with a high creep strength. When seen in the direction of conveyance of the separation apparatuses 1, it can advantageously be provided that the diameter of the conical basic body 25 will increase and a gradient angle of the screw surfaces 21 will remain substantially constant, with a pitch of the screw conveyor 2 rising, as seen in the direction of conveyance of the separation apparatuses 1. In this way there can be a continuous acceleration of the piece goods 5 in the direction of their longitudinal axis because the circumferential speed of the screw conveyor 2 at the tip of the cone is lower and will increase with increasing distance. It is advantageous in this respect that the conveying speed of the elongated piece goods will increase while the rotational speed of the screw conveyors 2 remains the same, through which the distance of directly 5 successively conveyed piece goods 5 will increase with increasing transverse conveyance along the separation apparatuses 1. It is advantageous that the pitch of the screw conveyor 2 can be small at the end of the separation apparatus 1 facing the first conveyor, through which it can be ensured that merely one piece good 5 is reliably grasped. It can thus be ensured in an especially reliable way that the individual piece goods 5 are separated from one another and are output or transferred at a predetermined distance from one another at the conveying end of the separation apparatuses 1. According to the preferred embodiment, the separation apparatus 1 comprises five screw conveyors 2, with the distances between the adjacent screw conveyors 2 preferably being constant. Piece goods 5 of different longitudinal extension can thus be separated simply and securely, with the minimum length of the piece goods 5 being substantially determined by the distance of two adjacent screw conveyors 2. The maximum length can be determined by the width of the separation apparatus 1. It can be provided that the piece goods 5 can protrude laterally beyond the separation apparatus by a predetermined amount. In other embodiments, 2, 3, 4, 6 or more screw conveyors can be arranged in the separation apparatus. The common guide means 22 is substantially defined by at least two guide points, with each of the at least two screw conveyors 2 comprising substantially one guide point for guiding the piece goods 5 and with the piece goods 5 being in sliding contact with at least two of the at least two guide points during the conveyance by means of the separation apparatus 1. Five screw conveyors 21 are arranged adjacent to one another in the preferred embodiment. Depending on the length and geometry of the piece goods 5, the piece goods 5 can be in sliding contact with two to five guide points. The five guide points can be disposed substantially on a straight line in the top view of the separation apparatus 1. The common guide means 22 can thus be arranged in a substantially straight line. The separation apparatus is thus especially suitable for substantially straight elongated piece goods 5 such as planks, sections and/or logs.

6 It can be provided in an advantageous further development that the regions of the screw surfaces 21 which fonn the guide means 22 are arranged substantially parallel to the longitudinal direction of the guide means 22. This can be arranged in an especially simple manner in such a way that the rotational axis 24 of the screw conveyor 2 encloses an angle according to the right angle minus the pitch of the screw surface 21 in relation to the longitudinal extension of the piece goods 5 disposed in the conveying position. Furthermore, the guide points arranged for contact with the piece goods 5 are disposed in this region of the screw surface 21. In this arrangement of the screw conveyor 2, the screw surface 21 is arranged substantially parallel to the longitudinal extension of the piece goods 2 in the region about the guide point. This allows the substantially parallel contact between the piece goods 5 and the screw surface 21. Good guidance can be ensured in combination with low load for the piece good 5 and the separation apparatus 1. Alternatively, the regions of the screw surface 21 forming the guide means 22 can be arranged by means of movable, especially twistable and resiliently held, lamellae along the screw surface 21, thus ensuring secure contact even in the case of piece goods 5 with a non-constant cross section. As a result of the sliding contact of the screw surfaces 21 and the piece goods 5 in the guide points, several force components act on the piece goods 5. They are combined into an overall force component acting upon the piece goods 5. The overall force component may comprise components in a direction normal to the longitudinal extension and in a direction parallel to the longitudinal extension of the piece goods 5. In an overall force component in a direction parallel to the longitudinal extension of the piece goods 5, the piece goods 5 can be accelerated and/or conveyed in the longitudinal direction. It can be provided advantageously that the screw conveyors 2, when seen in the operating position, are arranged for lifting the elongated piece goods 5. The maximum inclination of the screw conveyor 2 in relation to the horizontal line can be up to 45' for lifting. The maximum possible inclination can be limited substantially by the height extension of the screw surface 7 21, i.e. the extension from the basic body up to the outer end of the screw surface in the direction normal to the rotational axis 24 and the outside geometry of the piece goods 5 to be conveyed. According to the preferred embodiment, the inclination for lifting is approximately 15*. Alternatively, the inclination can also be 100 or 250 for example, or the screw conveyors 2 can be arranged in relation to the horizontal line without any inclination. Preferably, the rotational axes 24 of the screw conveyors 2 can be arranged in a substantially parallel way. As a result, substantially identical screw conveyors 2 can be arranged adjacent to one another and can be used for conveying and separating the piece goods 5. Alternatively, screw conveyors 2 with screw surfaces 21 of different slope can be arranged next to one another, with the rotational axes 24 of the adjacently arranged screw conveyors preferably not being arranged in parallel in this case. The piece goods 5 can thus be twisted in the screw conveyor 2 about a predetermined angle, when seen in a top view of the separation apparatus 1. It can be provided in a further alternative development of the screw conveyor 2 that the slope of the screw surface 21 increases with increasing distance from the first conveyor, in a substantially continuous manner. The conveying speed of the piece goods 5 can increase in a substantially continuous manner at constant angular speed of the screw conveyors 2. Figs. 1 and 2 also show a transport system 4 for elongated piece goods 5 with the first transversal transporter 31, with a separation apparatus 2 according to the preferred embodiment being arranged downstream of the first transversal transporter 31, as seen in the direction of transport. Figs. 1 and 2 further also show a transport system 4 for elongated piece goods, with the separation apparatus 2 according to the preferred embodiment being provided upstream of the first longitudinal transporter 61.

8 In particular, the first transversal transporter 31 can be arranged upstream of the separation apparatus 2 in the preferred embodiment of the separation apparatus 2 and the first longitudinal transporter 61 can be arranged downstream of the separation apparatus 2. In this connection, the screw conveyors 2 can rotate in operation especially in the same direction, with an overall force component forming in the piece goods 5 parallel to the longitudinal extension of the piece goods 5 as a result of the sliding contact between screw surfaces 21 and piece goods 5. As a result, the piece goods 5 are also conveyed parallel to the longitudinal extension in addition to the conveyance of the piece goods 5 transversally to their longitudinal extension. The piece goods 5 can thus be accelerated in the longitudinal direction, with the relative speed between the speed of a conveying means of the longitudinal transporter 61 and the conveying speed of the piece goods 5 in the longitudinal direction being reduced. The loads on the piece goods 5 and the contact during the transfer in the transfer region on the longitudinal transporter 61 can be kept at a low level. Alternatively, the separation apparatus 2 can be provided upstream and downstream of the longitudinal transporter, upstream and downstream of the transversal transporter, which means a first transversal transporter 31 can be provided upstream and a second transversal transporter can be provided downstream, or a second longitudinal transporter can be provided upstream and a second transversal transporter can be provided downstream. It can be provided advantageously that screw conveyors 2 are provided upstream with a receiving apparatus 11 for receiving the elongated piece goods 5 from the first transversal transporter 31. As a result, this ensures low loads on the separation apparatus and/or the transport system during the transfer of the elongated piece goods 5 from the upstream conveyor. It can be provided in this connection that the receiving apparatus 11 is arranged as a first chute 12. The first chute 12 can ensure an especially simple transfer and ensure that the loads on the separation apparatus 1 and/or the first conveyor are especially low during the transfer of the piece goods 5.

9 It can be provided in a further development that the receiving device 11 has a limiting element 13 for reducing the effective engagement length of the screw conveyors 2 depending on the cross-sectional size of the piece goods 5. It can thus be ensured that the engagement length of the screw conveyors 2 corresponds substantially to the maximum transversal extension and/or the diameter of the piece goods 5. The engagement length can be between 0.5 times and 1.5 times the diameter, especially in the piece goods 5 with round cross section. It can thus be ensured that merely one piece good 5 will be received by the screw conveyors, thus ensuring a secure separation of the piece goods 5 even in the case of successive piece goods 5 of different cross section. It can be provided in this connection that the limiting element 13 comprises a resiliently held lifting strip 14, through which the reduction of the effective engagement length of the screw conveyors 2 depending on the cross-sectional size of the piece goods 5 can occur in an especially simple way. The functionality of the lifting strip 14 can be arranged advantageously as follows according to the preferred embodiment as shown in Figs. 1 and 2: The piece good 5 lies in the first chute 12 and would slide through gravity into the separation device 1. The lifting element 13, especially the lifting strip 14, represents a limit stop for the piece good 5 at a predetermined position, with the piece good 5 unable to slide farther than up to said limit stop. The distance between the first end of the screw conveyor 2 facing the first conveyor and the limit stop substantially forms the predeterminable engagement length of the screw conveyor 2. The lifting strip 14 can be resilient, so that the limit stop will change automatically in the case of larger and heavier piece goods 5. In this way, differently large piece goods can be handled at once, and it can be ensured that only one each of the piece goods 5 will come into engagement with the guide means 22. The limiting element 13 can be arranged alternatively as an actuator and guide and/or allow the piece goods 5 to pass up to a predetermined delivery position.

10 The engagement length of the screw conveyor 2 in relation to one another has advantageously the same length. It can thus be ensured that the piece goods 5 will be transferred to the separation apparatus 1 in an aligned way. It can be provided advantageously that each screw conveyor 2 is associated with at least one limiting element 13. The predetermined delivery position of the piece goods 5 can thus be ensured even in the case of different lengths of the piece goods 5. It can further be provided advantageously that the screw conveyors 2 are provided downstream with a transfer device 15 for transferring the elongated piece goods 5. In this way, the low load on the separation apparatus 1 and/or the transport system can be ensured during the transfer of the elongated piece goods 5 to the downstream conveyor. In this connection, the transfer device 15 can be arranged as a second chute 16. An especially low load can thus be ensured during this transfer. In a further preferred embodiment (not shown), the guide means 22 can be delimited at least on one side by a stop rail. As a result, the overall force component of the piece goods 5 can be used in the longitudinal direction of the piece goods 5 for aligning the piece goods 5 in that the piece goods are moved against the stop rail and are pressed in a positive manner. In this connection it can be provided that the stop rail is arranged in merely one partial section of the separation apparatus facing the first conveyor. When the screw conveyors 2 rotate in the same direction, the piece goods 5 can be aligned in this partial section and can be accelerated in the following section of the separation apparatus 1 in the longitudinal direction. The alignment of the piece goods 5 and the reduction of the relative speed of the piece goods 5 in relation to the first longitudinal conveyor 61 can thus be ensured. In a preferred embodiment of the separation apparatus 1, the piece goods 5 are supplied in the transport system transversally to the longitudinal extension of the piece goods 5 by means of first transversal conveyor 31 which is provided upstream of the separation apparatus 1. The piece goods 5 are transferred to several (especially five) screw conveyors 2 by means of 11 first chute 12. A method for separating elongated piece goods 5, especially piece goods 5 of different lengths and different cross sections, can thus be performed by means of the separation apparatus 1. It is provided in the method for separating elongated piece goods 5 that the piece goods 5 are received by at least two adjacently arranged screw conveyors 2, with the piece goods 5 being received by at least one common guide means 22 formed by the screw surfaces 21 of the screw conveyor 2, and the piece goods 5 are driven by a rotation of the screw conveyor 2 with a movement component which is normal to the longitudinal axis of the piece goods 5. Following the separation by means of the separation apparatus 1, the separated piece good 5 is now transferred again, which is now the downstream conveyor, especially the first longitudinal conveyor 61. In an especially advantageous embodiment of the method it can be provided that the screw conveyors 2 are driven in the same direction and the piece goods 5 are driven additionally with a movement component in the direction of the longitudinal axis of the piece goods 5. Alternatively, two screw conveyors 2 can be driven in a diametrically opposed direction, but with the same circumferential speed, with the screw surfaces 21 of the two screw conveyors 2 being arranged especially with a diametrically opposed slope, e.g. right-hand or left-hand with the same pitch. As a result, the formation of the overall force component and the movement component in the piece goods 5 in the direction towards the longitudinal extension of the piece goods 5 can be prevented as far as possible, through which the piece goods 5 can be conveyed without any further retaining mechanisms, e.g. free from stop rails, without any noteworthy motion in the direction of the longitudinal extension of the piece goods 5 through the separation apparatus 1, especially from the receiving device 11 to the transfer device 15. In this connection, an even number of screw conveyors 2 can be preferably arranged, with two screw conveyors 2 being able to rotate in an opposite direction. The overall force component in the piece goods 5 can be especially low in the direction of the longitudinal extension of the piece goods 5 in the case of conveyance by means of the screw conveyors 2.

12 In a further advantageous embodiment which is not shown, several separation apparatuses I can be arranged in the installation, especially in the transport system, parallel next to one another, as seen in the direction of transport of the piece goods 5. The throughput of the transport system can thus be increased. In an alternative advantageous- embodiment which is not shown, several separation apparatuses 1 can be arranged in the installation, especially in the transport system, in a serially successive manner, as seen in the direction of transport of the piece goods 5. Several separations can thus be performed successively. A processing step can especially be performed on the piece goods 5 between the two separations. Further advantageous embodiments merely have a part of the described features, with any combination of features, which especially also include those of different described embodiments, being provided.

Claims (14)

1. A conveyor system for elongated piece goods, comprising a first cross conveyor for transporting the elongated piece goods in transversal orientation in a first conveying direction, and a separation apparatus, located downstream in conveying direction of the elongated piece goods at the first cross conveyor, for separating and removing the elongated piece goods delivered from the first cross conveyor, wherein the separation apparatus comprises at least two screw conveyors ranged next to one another, with screw surfaces of the at least two screw conveyors forcing at least one common guide for the elongated piece goods, the common guide being delimited at least on one side by a stop rail, wherein the stop rail is provided solely in that partial area of the separating apparatus facing the first cross conveyor.

2. A conveyor system according to claim 1, wherein the screw conveyors have a substantially conical basic body.

3. Conveyor system according to claim 1 or 2, wherein the areas of the screw surfaces which form the guide are arranged substantially parallel to the longitudinal direction of the guide.

4. Conveyor system according to claim 1, 2 or 3, wherein the screw conveyors, as seen in the operating position, are arranged for lifting the elongated piece goods.

5. Conveyor system according to any one of claim 1 to 4, wherein the screw conveyors have rotational axes that are arranged substantially parallel with respect to each other.

6. Conveyor system according to any one of claims 1 to 5, further including a receiving device located upstream of the screw conveyors for receiving the elongated piece goods form the first cross conveyor and directing these to the screw conveyors.

7. Conveyor system according to claim 6, characterized in that the receiving device is devised as a first chute. 14

8. Conveyor system according to claim 6 or 7, wherein the receiving device comprises a limiting element for reducing the effective engagement length of the screw conveyors depending on the cross-sectional size of the elongated piece goods.

9. Conveyor system according to claim 8, wherein the limiting element comprises a resiliently held lifting strip.

10. Conveyor system according to any one of claims 1 to 9, wherein a transfer device for transferring the elongated piece goods away from the screw conveyors is provided downstream of the screw conveyors.

11. Conveyor system according to claim 10, wherein the transfer device is devised as a second chute.

12. Conveyor according to any one of claims I to 11, further including a first longitudinal conveyor provided downstream of the separation apparatus.

13. Conveyor system according to any of claims I to 11, wherein a second cross conveyor is provided downstream of the separation apparatus.

14. Conveyor system according to any one claims 1 to 13, wherein all screw conveyors have the same direction of rotation.